[V8] ANOTHER V8 won't start...and I am stumped!

[dsaad at icehouse.net]

First off I would:
- Test fuel pressure for both too high or too low condition.
- Test fuel pressure regulator to make sure fuel is not comming out of the
vacuum line (indicating a bad regulator).
- Take a fuel sample (during pressure test) and look for water

Keep in mind this motor is very persnickety about its plugs. Mine had all sorts
of starting problems with Bosch +4 plugs, but does fine with even cheapo
Champions.

I would also be tempted to do a compression test because of the fast crank.
Mine also did this and I concluded (probably erroneously) that the rings had
carboned up and a cleaning job with "GM Top Engine Cleaner" loosened things up.
I had low compression with a cold motor but normal compression when hot or with
added oil to the cylinders during the cold test. As I recall, the cold
compression came up quite a bit after the cleaning.
I also had a sticky fuel pump relay. In my case, the motor would seem to want to
catch just as I released the key from cranking. I fiddled with the relay
contacts a little had that problem went away.

Dave

Quoting Ben Howell <bhowell at rmi.net>:

> Yep, another V8 that won't start......
>
> Here's the situation: The car is a 91' 5 speed that doesn't get driven a
> lot. Timing belt water pump and rebuilt heads went on less than 15k miles
> ago. Plug wires, caps, rotors, plugs were done at the same time. About 3
> weeks ago, I started it up to move it in the driveway and after about 4-5
> seconds of running, it just died. I tired to restart it and it doesn't even
> try. It turns over fast, like it has no compression or like the timing belt
> is broken. Fearing the worst, I pull a the driver's side timing belt cover
> for inspection and the belt is fine. My next suspect is the reference
> sender. I know they go bad all the time as I have now put two in this car.
> The one that is in there is less than 10k miles old, but I swap in a known
> good one anyway...same result, no start, fast crank.
>
> So, feeling dejected and defeated, I walk away and leave the car. Finally
> this weekend I get the chance to dig into it and see what I can see and here
> is where I am at:
>
> I get only one code and it is Intake Temp Sender. I KNOW that won't kill the
> car, but I check resistance and it is within spec AND I swap in a known good
> one. Still no start.
>
> Now I fear a timing belt jump. I pull both caps and both valve covers and
> bring crank up on TDC. All cams and distributors are in time. Nothing has
> skipped anywhere.
>
> I stick a spark plug in a wire end and crank....I see a spark, so now I know
> I have a good spark. Still no start.
>
> Now, I run the output test to see if the injectors are firing. All 8
> injectors pass the output test (or at least the click like they are supposed
> to). Still no start.
>
> Now I pull the plugs out. All 8 plugs range from extremely to somewhat
> fouled. So, I replace all 8 plugs with new units. Now it's almost like it
> wants to start. I can hear it trying to catch, but then it just starts to
> crank fast again. So, I pull all the plugs back out and they are soaked in
> fuel. I blow all the gas off the plugs with compressed air, pull the fuel
> pump relay and crank it over for a few seconds to purge it. Now, I leave the
> car with the plugs out of it for 24 hours in the hopes of really drying the
> cylinders out. After 24 hours, I reinstall the plugs and hook all the plug
> wires up and try to start it. Again, it tries to catch every few seconds,
> but still won't and just ends up flooding again.
>
> So, here's the bottom line, I have seen a spark with my own two eyes, the
> plugs are covered in fuel, so there must be fuel and I know everything is in
> time....why will this thing not start? It makes no sense. Does anyone have
> ANY idea. Anything? I like to think of myself a being competent with these
> cars, but this one has me stumped.
>
> Any help is appreciated.
>
> Thanks!
> Ben
>
> P.S. I am still subscribed to the list, but I have not been getting list
> mail for months now. So, if you could either reply direct or CC me that
> would be great.
>
>
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